Revert of Add <link rel=preload> onload support for scripts and styles (patchset #11 id:200001 of https://codereview.chromium.org/1577073005/ )

Reason for revert:
it broke the compile step on the WebKit Linux Oilpan Builder: http://build.chromium.org/p/chromium.webkit/builders/WebKit%20Linux%20Oilpan%20Builder/builds/451

Original issue's description:
> Add <link rel=preload> onload support for scripts and styles
>
> This CL adds onload support for <link rel=preload> for scripts and styles.
>
> Support for other resource types will be added in a followup CL.
>
> BUG=552289
>
> Committed: https://crrev.com/f85424718ca7a8ea3f330141ee68b717ae02f2f0
> Cr-Commit-Position: refs/heads/master@{#369892}

TBR=japhet@chromium.org,yoav@yoav.ws
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=552289

Review URL: https://codereview.chromium.org/1595793002

Cr-Commit-Position: refs/heads/master@{#369897}

7 files changed, 27 insertions, 167 deletions

diff --git a/third_party/WebKit/Source/core/core.gypi b/third_party/WebKit/Source/core/core.gypi
index 146d839..4909759 100644
--- a/third_party/WebKit/Source/core/core.gypi
+++ b/third_party/WebKit/Source/core/core.gypi
@@ -1878,8 +1878,6 @@
             'loader/LinkLoader.cpp',
             'loader/LinkLoader.h',
             'loader/LinkLoaderClient.h',
-            'loader/LinkPreloadResourceClients.cpp',
-            'loader/LinkPreloadResourceClients.h',
             'loader/MixedContentChecker.cpp',
             'loader/MixedContentChecker.h',
             'loader/NavigationPolicy.cpp',
diff --git a/third_party/WebKit/Source/core/loader/DocumentLoader.cpp b/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
index 5dafb42..f17bb79 100644
--- a/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
+++ b/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
@@ -160,7 +160,7 @@ const KURL& DocumentLoader::url() const
     return m_request.url();
 }
 
-ResourcePtr<Resource> DocumentLoader::startPreload(Resource::Type type, FetchRequest& request)
+void DocumentLoader::startPreload(Resource::Type type, FetchRequest& request)
 {
     ResourcePtr<Resource> resource;
     switch (type) {
@@ -194,7 +194,6 @@ ResourcePtr<Resource> DocumentLoader::startPreload(Resource::Type type, FetchReq
 
     if (resource)
         fetcher()->preloadStarted(resource.get());
-    return resource;
 }
 
 void DocumentLoader::didChangePerformanceTiming()
diff --git a/third_party/WebKit/Source/core/loader/DocumentLoader.h b/third_party/WebKit/Source/core/loader/DocumentLoader.h
index a7731d2..ec58033 100644
--- a/third_party/WebKit/Source/core/loader/DocumentLoader.h
+++ b/third_party/WebKit/Source/core/loader/DocumentLoader.h
@@ -146,7 +146,7 @@ public:
 
     bool loadingMultipartContent() const;
 
-    ResourcePtr<Resource> startPreload(Resource::Type, FetchRequest&);
+    void startPreload(Resource::Type, FetchRequest&);
 
     DECLARE_VIRTUAL_TRACE();
 
diff --git a/third_party/WebKit/Source/core/loader/LinkLoader.cpp b/third_party/WebKit/Source/core/loader/LinkLoader.cpp
index 0b4f466..7db397a 100644
--- a/third_party/WebKit/Source/core/loader/LinkLoader.cpp
+++ b/third_party/WebKit/Source/core/loader/LinkLoader.cpp
@@ -90,19 +90,15 @@ void LinkLoader::linkLoadingErrorTimerFired(Timer<LinkLoader>* timer)
     m_client->linkLoadingErrored();
 }
 
-void LinkLoader::triggerEvents(const Resource* resource)
+void LinkLoader::notifyFinished(Resource* resource)
 {
+    ASSERT(this->resource() == resource);
+
     if (resource->errorOccurred())
         m_linkLoadingErrorTimer.startOneShot(0, BLINK_FROM_HERE);
     else
         m_linkLoadTimer.startOneShot(0, BLINK_FROM_HERE);
-}
-
-void LinkLoader::notifyFinished(Resource* resource)
-{
-    ASSERT(this->resource() == resource);
 
-    triggerEvents(resource);
     clearResource();
 }
 
@@ -188,57 +184,31 @@ Resource::Type LinkLoader::getTypeFromAsAttribute(const String& as, Document* do
     return Resource::LinkSubresource;
 }
 
-void LinkLoader::createLinkPreloadResourceClient(ResourcePtr<Resource> resource)
+static void preloadIfNeeded(const LinkRelAttribute& relAttribute, const KURL& href, Document& document, const String& as)
 {
-    if (!resource)
+    if (!document.loader())
         return;
-    switch (resource->type()) {
-    case Resource::Image:
-        break;
-    case Resource::Script:
-        m_linkPreloadResourceClient = LinkPreloadScriptResourceClient::create(this, toScriptResource(resource.get()));
-        break;
-    case Resource::CSSStyleSheet:
-        m_linkPreloadResourceClient = LinkPreloadStyleResourceClient::create(this, toCSSStyleSheetResource(resource.get()));
-        break;
-    // TODO(yoav): add support for everything below.
-    case Resource::Font:
-        break;
-    case Resource::Media:
-        break;
-    case Resource::TextTrack:
-        break;
-    case Resource::Raw:
-    case Resource::LinkSubresource:
-        break;
-    default:
-        ASSERT_NOT_REACHED();
-    }
-}
 
-static ResourcePtr<Resource> preloadIfNeeded(const LinkRelAttribute& relAttribute, const KURL& href, Document& document, const String& as)
-{
-    if (!document.loader() || !relAttribute.isLinkPreload())
-        return nullptr;
-
-    UseCounter::count(document, UseCounter::LinkRelPreload);
-    ASSERT(RuntimeEnabledFeatures::linkPreloadEnabled());
-    if (!href.isValid() || href.isEmpty()) {
-        document.addConsoleMessage(ConsoleMessage::create(OtherMessageSource, WarningMessageLevel, String("<link rel=preload> has an invalid `href` value")));
-        return nullptr;
+    if (relAttribute.isLinkPreload()) {
+        UseCounter::count(document, UseCounter::LinkRelPreload);
+        ASSERT(RuntimeEnabledFeatures::linkPreloadEnabled());
+        if (!href.isValid() || href.isEmpty()) {
+            document.addConsoleMessage(ConsoleMessage::create(OtherMessageSource, WarningMessageLevel, String("<link rel=preload> has an invalid `href` value")));
+            return;
+        }
+        Resource::Type type = LinkLoader::getTypeFromAsAttribute(as, &document);
+        ResourceRequest resourceRequest(document.completeURL(href));
+        ResourceFetcher::determineRequestContext(resourceRequest, type, false);
+        FetchRequest linkRequest(resourceRequest, FetchInitiatorTypeNames::link);
+
+        linkRequest.setPriority(document.fetcher()->loadPriority(type, linkRequest));
+        Settings* settings = document.settings();
+        if (settings && settings->logPreload())
+            document.addConsoleMessage(ConsoleMessage::create(OtherMessageSource, DebugMessageLevel, String("Preload triggered for " + href.host() + href.path())));
+        linkRequest.setForPreload(true);
+        linkRequest.setAvoidBlockingOnLoad(true);
+        document.loader()->startPreload(type, linkRequest);
     }
-    Resource::Type type = LinkLoader::getTypeFromAsAttribute(as, &document);
-    ResourceRequest resourceRequest(document.completeURL(href));
-    ResourceFetcher::determineRequestContext(resourceRequest, type, false);
-    FetchRequest linkRequest(resourceRequest, FetchInitiatorTypeNames::link);
-
-    linkRequest.setPriority(document.fetcher()->loadPriority(type, linkRequest));
-    Settings* settings = document.settings();
-    if (settings && settings->logPreload())
-        document.addConsoleMessage(ConsoleMessage::create(OtherMessageSource, DebugMessageLevel, String("Preload triggered for " + href.host() + href.path())));
-    linkRequest.setForPreload(true);
-    linkRequest.setAvoidBlockingOnLoad(true);
-    return document.loader()->startPreload(type, linkRequest);
 }
 
 bool LinkLoader::loadLinkFromHeader(const String& headerValue, Document* document, const NetworkHintsInterface& networkHintsInterface, CanLoadResources canLoadResources)
@@ -278,7 +248,7 @@ bool LinkLoader::loadLink(const LinkRelAttribute& relAttribute, CrossOriginAttri
     preconnectIfNeeded(relAttribute, href, document, crossOrigin, networkHintsInterface, LinkCalledFromMarkup);
 
     if (m_client->shouldLoadLink())
-        createLinkPreloadResourceClient(preloadIfNeeded(relAttribute, href, document, as));
+        preloadIfNeeded(relAttribute, href, document, as);
 
     // FIXME(crbug.com/323096): Should take care of import.
     if ((relAttribute.isLinkPrefetch() || relAttribute.isLinkSubresource()) && href.isValid() && document.frame()) {
@@ -326,7 +296,6 @@ void LinkLoader::released()
 DEFINE_TRACE(LinkLoader)
 {
     visitor->trace(m_prerender);
-    visitor->trace(m_linkPreloadResourceClient);
 }
 
 }
diff --git a/third_party/WebKit/Source/core/loader/LinkLoader.h b/third_party/WebKit/Source/core/loader/LinkLoader.h
index 2b146b1..bb79b8e 100644
--- a/third_party/WebKit/Source/core/loader/LinkLoader.h
+++ b/third_party/WebKit/Source/core/loader/LinkLoader.h
@@ -36,7 +36,6 @@
 #include "core/fetch/ResourceClient.h"
 #include "core/fetch/ResourceOwner.h"
 #include "core/loader/LinkLoaderClient.h"
-#include "core/loader/LinkPreloadResourceClients.h"
 #include "platform/CrossOriginAttributeValue.h"
 #include "platform/PrerenderClient.h"
 #include "platform/Timer.h"
@@ -67,8 +66,6 @@ public:
     void didSendLoadForPrerender() override;
     void didSendDOMContentLoadedForPrerender() override;
 
-    void triggerEvents(const Resource*);
-
     void released();
     bool loadLink(const LinkRelAttribute&, CrossOriginAttributeValue, const String& type, const String& as, const KURL&, Document&, const NetworkHintsInterface&);
     enum CanLoadResources { LoadResources, DoNotLoadResources };
@@ -80,7 +77,6 @@ public:
 private:
     void linkLoadTimerFired(Timer<LinkLoader>*);
     void linkLoadingErrorTimerFired(Timer<LinkLoader>*);
-    void createLinkPreloadResourceClient(ResourcePtr<Resource>);
 
     LinkLoaderClient* m_client;
 
@@ -88,7 +84,6 @@ private:
     Timer<LinkLoader> m_linkLoadingErrorTimer;
 
     OwnPtrWillBeMember<PrerenderHandle> m_prerender;
-    OwnPtrWillBeMember<LinkPreloadResourceClient> m_linkPreloadResourceClient;
 };
 
 }
diff --git a/third_party/WebKit/Source/core/loader/LinkPreloadResourceClients.cpp b/third_party/WebKit/Source/core/loader/LinkPreloadResourceClients.cpp
deleted file mode 100644
index 27c4bb4d..0000000
--- a/third_party/WebKit/Source/core/loader/LinkPreloadResourceClients.cpp
+++ /dev/null
@@ -1,17 +0,0 @@
-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "core/loader/LinkPreloadResourceClients.h"
-
-#include "core/loader/LinkLoader.h"
-
-namespace blink {
-
-void LinkPreloadResourceClient::triggerEvents(const Resource* resource) const
-{
-    if (m_loader)
-        m_loader->triggerEvents(resource);
-}
-
-}
diff --git a/third_party/WebKit/Source/core/loader/LinkPreloadResourceClients.h b/third_party/WebKit/Source/core/loader/LinkPreloadResourceClients.h
deleted file mode 100644
index 187f06c..0000000
--- a/third_party/WebKit/Source/core/loader/LinkPreloadResourceClients.h
+++ /dev/null
@@ -1,84 +0,0 @@
-// Copyright 2016 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef LinkPreloadResourceClients_h
-#define LinkPreloadResourceClients_h
-
-#include "core/fetch/CSSStyleSheetResource.h"
-#include "core/fetch/FontResource.h"
-#include "core/fetch/ImageResourceClient.h"
-#include "core/fetch/ResourceOwner.h"
-#include "core/fetch/ScriptResource.h"
-#include "core/fetch/StyleSheetResourceClient.h"
-
-namespace blink {
-
-class LinkLoader;
-
-class LinkPreloadResourceClient : public NoBaseWillBeGarbageCollectedFinalized<LinkPreloadResourceClient> {
-public:
-    virtual ~LinkPreloadResourceClient() { }
-
-    void triggerEvents(const Resource*) const;
-
-protected:
-    LinkPreloadResourceClient(LinkLoader* loader)
-        : m_loader(loader)
-    {
-        ASSERT(loader);
-    }
-
-private:
-    LinkLoader* m_loader;
-};
-
-class LinkPreloadScriptResourceClient: public LinkPreloadResourceClient, public ResourceOwner<ScriptResource, ScriptResourceClient> {
-public:
-    static PassOwnPtr<LinkPreloadScriptResourceClient> create(LinkLoader* loader, ScriptResource* resource)
-    {
-        return adoptPtr(new LinkPreloadScriptResourceClient(loader, resource));
-    }
-
-    virtual String debugName() const { return "LinkPreloadScript"; }
-
-    void notifyFinished(Resource* resource) override
-    {
-        ASSERT(this->resource() == resource);
-        triggerEvents(resource);
-    }
-
-private:
-    LinkPreloadScriptResourceClient(LinkLoader* loader, ScriptResource* resource)
-        : LinkPreloadResourceClient(loader)
-    {
-        setResource(resource);
-    }
-};
-
-class LinkPreloadStyleResourceClient: public LinkPreloadResourceClient, public ResourceOwner<CSSStyleSheetResource, StyleSheetResourceClient> {
-public:
-    static PassOwnPtr<LinkPreloadStyleResourceClient> create(LinkLoader* loader, CSSStyleSheetResource* resource)
-    {
-        return adoptPtr(new LinkPreloadStyleResourceClient(loader, resource));
-    }
-
-    virtual String debugName() const { return "LinkPreloadStyle"; }
-
-    void setCSSStyleSheet(const String&, const KURL&, const String&, const CSSStyleSheetResource* resource) override
-    {
-        ASSERT(this->resource() == resource);
-        triggerEvents(static_cast<const Resource*>(resource));
-    }
-
-private:
-    LinkPreloadStyleResourceClient(LinkLoader* loader, CSSStyleSheetResource* resource)
-        : LinkPreloadResourceClient(loader)
-    {
-        setResource(resource);
-    }
-};
-
-}
-
-#endif // LinkPreloadResourceClients_h